-x+y-2=0当y=0x=?x=0y=?
当x、y满足x>=0,y>=x,2x+y+k
线性规划 当x.y满足x>=0,y
当x,y满足条件x>=0,y
设Z=X+Y,其中X,Y满足X+2Y>=0,X-Y
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
设x>1,y>0,若x^y+x^-y=2根号2,则x^y-x^-y等于
变量x,y满足x-2y=0,x
若线段x ,y 满足[2x-3y]*[3x+2y]=0 则x/y=?怎样算出2x-3y=0或3x+2y=0 当2x-3y
x,y属于R 且f(x)+f(y)=f(x+y)恒成立 当x>0,f(x)
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
matlab 有个关系式y=x,当x>0时,y=0,当x